Funds are requested to support eight pre-doctoral (Ph.D. candidates) and six postdoctoral trainees in the Training Program in Environmental Toxicology, the long-standing training component of the Center in Molecular Toxicology at Vanderbilt University. This interdisciplinary program provides research career training in molecular aspects of toxicology related to environmental health. Because the field is inherently interdisciplinary, research training in the program spans chemistry, biochemistry, chemical biology, structural biology, analytical technology, functional genomics, pathogen-host interactions, disease pathology, and exposure science. The faculty preceptors have appointments in the departments of Biochemistry, Biological Sciences, Biomedical Informatics, Chemistry, Medicine, Neurology, Pathology/Microbiology/Immunology, Pediatrics, and Pharmacology, all of whom train doctoral students and postdoctoral fellows. Training is achieved through basic and specialized coursework, research rotations, dissertation research, and participation in seminars, journal clubs, and joint research meetings. A distinctive feature of the Program is hands-on training on diverse technology platforms through a highly developed and open system of research facility cores at Vanderbilt. Graduate students are recruited to the Department of Chemistry through departmental mechanisms, with assistance from the Center in Molecular Toxicology. In the medical school departments, graduate students are initially recruited into either the Interdisciplinary Graduate Program in Biomedical and Biological Sciences or the Quantitative and Chemical Biology Program, where they spend the first 9 months in a common core curriculum and do laboratory rotations. Graduate students are supported for the first year by these programs. Students then are recruited into the Training Program in Environmental Toxicology from these first-year pools, and training program support begins in the second year. Both pre-doctoral and postdoctoral trainees are selected by the Training Program Advisory Committee, with guidelines to ensure distribution of trainees and monitoring of progress. The list of preceptors includes 18 faculty members who are all Investigators in the Center in Molecular Toxicology. Major research areas in the Center include oxidative damage, DNA damage and repair, maintenance of genomic integrity, enzymatic biotransformation and reactions of electrophiles, neurotoxicology, respiratory disease pathophysiology, systems biology, and pathogen-host interactions. Graduates from the program have been highly successful in academia, industry, and other professional settings and include leaders in the field.